LM_Sensors For ATI Graphics Cards

Back in February, AMD's John Bridgman had expressed hope in providing LM_Sensors support for monitoring the GPU temperature and fan speed on ATI graphics cards. He was hoping to get the needed documentation to the LM_Sensors project in March, but that hadn't happened and currently AMD's focus is on open-source R600/700 series 3D support. However, interest in LM_Sensors support for ATI graphics cards has been rejuvenated on the sensor project's mailing list.

The mailing list discussion was started by a user interested in having LM_Sensors support for his ATI hardware. Hans de Goede, an LM_Sensors contributor, then responded that on at least some graphics cards the hardware monitoring IC is on the Radeon multimedia i2c channel. LM_Sensors doesn't yet have a driver supporting the Radeon multimedia i2c channel as with some hardware (the ATI All-In-Wonder was named) this channel is also used by the graphics card.

Kernel mode-setting though will actually come to the rescue now with the mode-setting being in-kernel and eliminating the need for any user-space component to be tapping the registers. The way now to support this i2c channel is by exposing it in the DRM driver and the LM_Sensors should recognize the hardware monitoring adapter.

Michael Larabel is the principal author of Phoronix.com and founded the web-site in 2004 with a focus on enriching the Linux hardware experience and being the largest web-site devoted to Linux hardware reviews, particularly for products relevant to Linux gamers and enthusiasts but also commonly reviewing servers/workstations and embedded Linux devices. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics hardware drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated testing software. He can be followed via Twitter and Google+ or contacted via MichaelLarabel.com.